Chirp shotpoint navigation from USGS cruise 2003-003-FA along the inner continental shelf of northern North Carolina (isc2003003_shots.shp)

The northeastern North Carolina coastal system, from False Cape, Virginia, to Cape Lookout, North Carolina, has been studied by a cooperative research program that mapped the Quaternary geologic framework of the estuaries, barrier islands, and inner continental shelf. This information provides a basis to understand the linkage between geologic framework, physical processes, and coastal evolution at time scales from storm events to millennia. The study area attracts significant tourism to its parks and beaches, contains a number of coastal communities, and supports a local fishing industry, all of which are impacted by coastal change. Knowledge derived from this research program can be used to mitigate hazards and facilitate effective management of this dynamic coastal system. This regional mapping project produced spatial datasets of high-resolution geophysical (bathymetry, backscatter intensity, and seismic reflection) and sedimentary (core and grab-sample) data. The high-resolution geophysical data were collected during numerous surveys within the back-barrier estuarine system, along the barrier island complex, in the nearshore, and along the inner continental shelf. Sediment cores were taken on the mainland and along the barrier islands, and both cores and grab samples were taken on the inner shelf. Data collection was a collaborative effort between the U.S. Geological Survey (USGS) and several other institutions including East Carolina University (ECU), the North Carolina Geological Survey, and the Virginia Institute of Marine Science (VIMS). The high-resolution geophysical data of the inner continental shelf were collected during six separate surveys conducted between 1999 and 2004 (four USGS surveys north of Cape Hatteras: 1999-045-FA, 2001-005-FA, 2002-012-FA, 2002-013-FA, and two USGS surveys south of Cape Hatteras: 2003-003-FA and 2004-003-FA) and cover more than 2600 square kilometers of the inner shelf. Single-beam bathymetry data were collected north of Cape Hatteras in 1999 using a Furuno fathometer. Swath bathymetry data were collected on all other inner shelf surveys using a SEA, Ltd. SwathPLUS 234-kHz bathymetric sonar. Chirp seismic data as well as sidescan-sonar data were collected with a Teledyne Benthos (Datasonics) SIS-1000 north of Cape Hatteras along with boomer seismic reflection data (cruises 1999-045-FA, 2001-005-FA, 2002-012-FA and 2002-013-FA). An Edgetech 512i was used to collect chirp seismic data south of Cape Hatteras (cruises 2003-003-FA and 2004-003-FA) along with a Klein 3000 sidescan-sonar system. Sediment samples were collected with a Van Veen grab sampler during four of the USGS surveys (1999-045-FA, 2001-005-FA, 2002-013-FA, and 2004-003-FA). Additional sediment core data along the inner shelf are provided from previously published studies. A cooperative study, between the North Carolina Geological Survey and the Minerals Management Service (MMS cores), collected vibracores along the inner continental shelf offshore of Nags Head, Kill Devils Hills and Kitty Hawk, North Carolina in 1996. The U.S. Army Corps of Engineers collected vibracores along the inner shelf offshore of Dare County in August 1995 (NDC cores) and July-August 1995 (SNL cores). These cores are curated by the North Carolina Geological Survey and were used as part of the ground validation process in this study. Nearshore geophysical and core data were collected by the Virginia Institute of Marine Science. The nearshore is defined here as the region between the 10-m isobath and the shoreline. High-resolution bathymetry, backscatter intensity, and chirp seismic data were collected between June 2002 and May 2004. Vibracore samples were collected in May and July 2005. Shallow subsurface geophysical data were acquired along the Outer Banks barrier islands using a ground-penetrating radar (GPR) system. Data were collected by East Carolina University from 2002 to 2005. Rotasonic cores (OBX cores) from five drilling operations were collected from 2002 to 2006 by the North Carolina Geological Survey as part of the cooperative study with the USGS. These cores are distributed throughout the Outer Banks as well as the mainland. The USGS collected seismic data for the Quaternary section within the Albemarle-Pamlico estuarine system between 2001 and 2004 during six surveys (2001-013-FA, 2002-015-FA, 2003-005-FA, 2003-042-FA, 2004-005-FA, and 2004-006-FA). These surveys used Geopulse Boomer and Knudsen Engineering Limited (KEL) 320BR Chirp systems, except cruise 2003-042-FA, which used an Edgetech 424 Chirp and a boomer system. The study area includes Albemarle Sound and selected tributary estuaries such as the South, Pungo, Alligator, and Pasquotank Rivers; Pamlico Sound and trunk estuaries including the Neuse and Pamlico Rivers; and back-barrier sounds including Currituck, Croatan, Roanoke, Core, and Bogue.针对北卡罗来纳州东北部沿海系统（范围涵盖弗吉尼亚州假角至北卡罗来纳州卢考特角），一项合作研究项目已完成其河口、障壁岛及内陆陆架的第四纪地质框架填绘工作。该研究成果为理解地质框架、物理过程与海岸演化在从风暴事件到千年尺度的时间范围内的内在关联提供了科学依据。该研究区域内的公园与海滩吸引了大量游客，分布有多个沿海聚居区，并支撑着当地渔业，所有这些活动均受到海岸变化的影响。本研究项目所获得的认知可用于减缓海岸灾害风险，并助力该动态海岸系统的有效管理。 本区域填绘项目产出了多套空间数据集，涵盖高分辨率地球物理数据（水深测量、背散射强度与地震反射数据）及沉积数据（岩心与抓取沉积物样品数据）。高分辨率地球物理数据采集于障壁岛后河口系统、障壁岛复合体、近岸区域及内陆陆架的多次勘测作业中。沉积岩心采集于大陆及障壁岛区域，而岩心与抓取沉积物样品均采集于内陆陆架。数据采集工作由美国地质调查局（U.S. Geological Survey, USGS）与东卡罗来纳大学（East Carolina University, ECU）、北卡罗来纳州地质调查局、弗吉尼亚海洋科学研究所（Virginia Institute of Marine Science, VIMS）等多家机构合作完成。 内陆陆架的高分辨率地球物理数据采集于1999年至2004年间开展的6次独立勘测中：其中4次USGS勘测位于哈特拉斯角以北（航次编号：1999-045-FA、2001-005-FA、2002-012-FA、2002-013-FA），另外2次USGS勘测位于哈特拉斯角以南（航次编号：2003-003-FA与2004-003-FA），覆盖面积超过2600平方千米的内陆陆架区域。1999年，研究人员使用古野（Furuno）测深仪在哈特拉斯角以北区域采集了单波束水深数据。其余所有内陆陆架勘测均使用SEA有限公司SwathPLUS 234-kHz测深声呐采集条带水深数据。哈特拉斯角以北区域使用泰利迪本托斯（Teledyne Benthos, Datasonics）SIS-1000采集啁啾地震数据与侧扫声呐数据，并在1999-045-FA、2001-005-FA、2002-012-FA及2002-013-FA航次中采集电火花震源地震反射数据。在哈特拉斯角以南的2003-003-FA与2004-003-FA航次中，研究人员使用Edgetech 512i采集啁啾地震数据，并搭配Klein 3000侧扫声呐系统。在4次USGS勘测（航次编号：1999-045-FA、2001-005-FA、2002-013-FA及2004-003-FA）中，研究人员使用范维恩（Van Veen）抓取采样器采集了沉积物样品。内陆陆架的额外沉积岩心数据来自已发表的相关研究。 1996年，北卡罗来纳州地质调查局与矿产管理局（Minerals Management Service, MMS岩心）合作开展的一项研究，在北卡罗来纳州纳格斯黑德、基尔迪维尔希尔斯与基蒂霍克近海的内陆陆架采集了振动岩心样品。美国陆军工程兵团于1995年8月（NDC岩心）及1995年7-8月（SNL岩心）在戴尔县近海的内陆陆架采集了振动岩心样品。上述岩心由北卡罗来纳州地质调查局保存，并作为本研究地面验证工作的组成部分。 近岸地球物理与岩心数据由弗吉尼亚海洋科学研究所（VIMS）采集。本研究中近岸定义为10米等深线与海岸线之间的区域。2002年6月至2004年5月间，研究人员采集了高分辨率水深、背散射强度及啁啾地震数据。2005年5月与7月采集了振动岩心样品。 东卡罗来纳大学于2002年至2005年间，使用探地雷达（ground-penetrating radar, GPR）系统对外岸障壁岛开展了浅地表地球物理数据采集工作。北卡罗来纳州地质调查局于2002年至2006年间，在与美国地质调查局（USGS）的合作研究中，通过5次钻探作业获取了旋转声波岩心（OBX岩心）。这些岩心分布于外岸区域及大陆地带。 美国地质调查局（USGS）于2001年至2004年间开展了6次勘测（航次编号：2001-013-FA、2002-015-FA、2003-005-FA、2003-042-FA、2004-005-FA及2004-006-FA），对阿尔伯马尔-帕姆利科河口系统内的第四纪地层采集了地震数据。除2003-042-FA航次使用Edgetech 424啁啾系统与电火花震源系统外，其余航次均使用Geopulse电火花震源与克努森工程有限公司（Knudsen Engineering Limited, KEL）320BR啁啾系统。本研究区域包括阿尔伯马尔湾及南河、庞戈河、阿勒加托河与帕斯科坦克河等选定支流河口；帕姆利科湾及纽斯河、帕姆利科河等主干河口；以及科里塔克湾、克罗阿坦湾、罗阿诺克湾、科尔湾与博格湾等障壁岛后海湾。